Synthesis and Fluorescence Properties of Rare Earths Doped Fluorides and Nanocomposites of Luminescence

Synthesis and Fluorescence Properties of Rare Earths Doped Fluorides and Nanocomposites of Luminescence
　　In the dissertation, nanoparticles of YF3:Eu, YF3:Tb, YF3:Ce and YF3:Er were prepared from the quaternary microemulsions of CTAB, n-butanol, n-octance and water based .The X-ray diffraction (XRD) patterns were indexed to a pure YF3 orthorhombic phase. Envrionment scanning electron microscopy (ESEM) images showed spherical YF3:Eu,YF3:Tb,YF3:Ce and YF3:Er nanoparticles which were about 13-40 nm in diameter.The emission of YF3: Eu nanoparticles peaked at 592 nm attributed to Eu3+ 5D0→7F1 transition.The emission of YF3:Tb neodymium magnets nanoparticles peaked at 544 nm attributed to Tb3+ 5D4→7F5 transition which is the green transition emission of 5D4 level.The emission peak of YF3:Ce nanoparticles located at 340 nm belong to luminesence of near ultraviolet.The emission of YF3: Er peaked at 1547nm. There is red shift and up-conversion in YF3:Er nanoparticles which emits red and green.The synthesis of YF3:Eu/PMMA and YF3:Tb/PMMA composite materials were primarily studied. Compared to YF3:Eu and YF3:Tb http://www.chinamagnets.biz/ nanoparticles, the emission and excitation peaks do not change but the intensity weaken of YF3:Eu and YF3:Tb nanoparticles and PMMA composite materials by the fluorescent spectra.